symbol highlighting problem

So I've been researching this for a long time, couldn't find anything so I'm making the complaint myself
there's this problem that when I enter a symbol, the background just doesn't lighten up! It's been rathen frustrating to deal with, since I thought it was an animate problem but no! When I tried to enter the symbol in flash cs6, it did the same thing.
[I will try to provide screenshots below]

at this point I just think it's an option I turn on with a hot key or something, if so, tell me please.